This invention relates to one side coating of a moving strip of material with a fluid coating material. The moving strip may be metal, fabric or other substantially impervious material, and may be of any width or thickness. The coating fluid may be a molten metal, paint, lacquer or other fluid which will solidify as by reduction in temperature and/or passage of time. However, in the attached drawings and the following specification the invention will be specifically illustrated and described as applied to the continuous one side galvanizing of steel strip.
Various procedures for the production of such a product have been proposed as it has been recognized that one side galvanized steel sheet is most desirable for uses, such as automobile bodies, where a paint or other surface finish must be applied directly to the steel surface on one side and the opposite side must be protected against corrosion. In one prior procedure, one side of the strip has been coated with a protective material which will prevent the adherence of molten zinc to that side and the strip then passed through a pot of molten zinc in which the zinc adheres in the usual manner to the other side. This is followed by chemical or physical removal of the coating on the first side. In another prior proposal for the production of one side galvanized steel strip, a roller has been partially immersed in a pot of molten zinc and the strip moved over the roller with one side thereof in contact therewith. However, difficulty is encountered because of the tendency of the molten zinc to travel over the edges of the strip of the opposite side. In some cases, the edges have been trimmed after coating but this is an expensive and wasteful procedure.